Outputs (12)
An imperfect double: probing the physical origin of the low-frequency quasi-periodic oscillation and its harmonic in black hole binaries (2013)
Journal Article
We extract the spectra of the strong low-frequency quasi-periodic oscillation (QPO) and its harmonic during the rising phase of an outburst in the black hole binary XTE J1550-564. We compare these frequency-resolved spectra to the time-averaged spect... Read More about An imperfect double: probing the physical origin of the low-frequency quasi-periodic oscillation and its harmonic in black hole binaries.
The story of Seyfert galaxy RE J2248-511: from intriguingly ultrasoft to unremarkably average (2013)
Journal Article
RE J2248−511 is one of only 14 non-blazar active galactic nuclei (AGN) detected in the far-ultraviolet (FUV) by the ROSAT Wide Field Camera implying a large ultrasoft X-ray flux. This soft X-ray excess is strongly variable on year time-scales, a comm... Read More about The story of Seyfert galaxy RE J2248-511: from intriguingly ultrasoft to unremarkably average.
What powers the most relativistic jets? – I. BL Lacs (2013)
Journal Article
The dramatic relativistic jets pointing directly at us in BL Lacertae (BL Lac) objects can be well modelled by bulk motion beaming of synchrotron self-Compton emission powered by a low Eddington fraction accretion flow. Nearly 500 of these active gal... Read More about What powers the most relativistic jets? – I. BL Lacs.
The soft component and the iron line as signatures of the disc inner radius in Galactic black hole binaries (2013)
Journal Article
The inner radius of the accretion disc around a black hole in the low/hard state can be measured in one of two ways. First, via the extent of broadening of the iron emission line, and secondly, from the luminosity and temperature of the weak soft com... Read More about The soft component and the iron line as signatures of the disc inner radius in Galactic black hole binaries.
Jets and the accretion flow in low-luminosity black holes (2013)
Journal Article
The X-ray spectra of black hole binaries (BHB) in the low/hard state (LHS) first harden as the flux decreases, then soften. This change in behaviour has been variously attributed to either the X-rays switching from being produced in the flow to being... Read More about Jets and the accretion flow in low-luminosity black holes.
A new way to measure supermassive black hole spin in accretion disc-dominated Active Galaxies (2013)
Journal Article
We show that disc continuum fitting can be used to constrain black hole spin in a subclass of narrow-line Seyfert 1 (NLS1) active galactic nuclei as their low mass and high mass accretion rate means that the disc peaks at energies just below the soft... Read More about A new way to measure supermassive black hole spin in accretion disc-dominated Active Galaxies.
The effect of advection at luminosities close to Eddington: The ULX in M 31 (2013)
Journal Article
Highly Ionized Fe-K Absorption Line from Cygnus X-1 in the High/Soft State Observed with Suzaku (2013)
Journal Article
We present observations of a transient He-like Fe Kα absorption line in Suzaku observations of the black hole binary Cygnus X-1 on 2011 October 5 near superior conjunction during the high/soft state, which enable us to map the full evolution from the... Read More about Highly Ionized Fe-K Absorption Line from Cygnus X-1 in the High/Soft State Observed with Suzaku.
Fast variability as a probe of the smallest regions around accreting black holes (2013)
Journal Article
We extract the spectra of the fastest variability (above 10 Hz) from the black hole XTE J1550−564 during a transition from hard to soft state on the rise to outburst. We confirm previous results that the rapid variability contains no significant disc... Read More about Fast variability as a probe of the smallest regions around accreting black holes.
Bright radio emission from an ultraluminous stellar-mass microquasar in M 31 (2013)
Journal Article
A subset of ultraluminous X-ray sources (those with luminosities of less than 1040 erg s−1; ref. 1) are thought to be powered by the accretion of gas onto black holes with masses of ~5–20 , probably by means of an accretion disk2, 3. The X-ray and ra... Read More about Bright radio emission from an ultraluminous stellar-mass microquasar in M 31.